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1.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more.  相似文献   
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Steven French 《Synthese》1989,78(2):141-166
Faced with strong arguments to the effect that Leibniz'sPrinciple of the Identity of Indiscernibles (PII) is not a necessary truth, many supporters of the Principle have staged a strategic retreat to the claim that it is contingently true in this, the actual, world. The purpose of this paper is to examine the status of the various forms of PII in both classical and quantum physics, and it is concluded that this latter view is at best doubtful, at worst, simply wrong.I would like to thank Michael Redhead and an anonymous referee for several useful suggestions and criticisms relating to the earlier version of this paper. I must also acknowledge the support given by the Centre of Logic, Epistemology and History of Science of the University of Campinas and the Brazilian National Council for Scientific and Technological Development in the later stages of the preparation of this work.  相似文献   
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Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
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In 1985 we published a meta-analysis of gender differences across age in motor performance in Psychological Bulletin, but it did not include an indexing of each motor task to the references from which it was obtained. This paper provides a table listing the 20 motor tasks and the references from which data for each task were taken. The range of tasks was from fundamental movements (e.g., catching, jumping, running, throwing) to motor fitness (e.g., agility, arm hang, balance, grip strength) to perceptual-motor abilities (e.g., anticipation timing, fine eye-motor coordination, pursuit-rotor tracking, reaction time). The arm hang was represented in the fewest papers (n = 2) while the dash and long jump were most frequently referenced (n = 21).  相似文献   
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The disambiguation of threat/neutral homophones was investigated in high- and low-trait anxiety subjects who had been exposed to either a positive or a negative mood manipulation procedure. Subjects were required first to spell each auditorily presented word and second, to generate and speak a sentence using the word. Difference indices were calculated for the spelling and the sentence usage data, i.e. the number of threat minus neutral interpretations. Examination of these indices revealed that subjects exposed to the negative mood manipulation procedure produced relatively more threat than neutral interpretations (for both spelling and sentence usage) than did subjects exposed to the positive mood manipulation procedure. Multiple regression analyses revealed that both the trait anxiety and mood manipulation variables contributed significantly to the prediction of the difference index on the spelling task. In the analysis of the use of homophones in sentences, only the mood manipulation variable contributed significantly to the prediction of the difference index on the sentence usage task.  相似文献   
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A survey of 158 18- to 24-yr. old college and 119 noncollege adults indicated that the latter were more reluctant to approve autopsies for spouses, children and distant relatives. Nonstudents also expressed more objections to autopsies than did students.  相似文献   
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Improving the situation of women includes more than simply updating laws to correspond to the modern woman's aspirations. It is just as important to bring about changes in attitudes. Understanding and acceptance of equality must be fostered through persuasion and logical argument in order to dispel traditional misconceptions. This paper reviews the history and current status of women and divorce in France.This article has been made available to the journal through the kindness of the French Embassy, Press and Information Division. The editor would like especially to thank Andre Baeyens, Director of the Press and Information Division, French Embassy, New York City.  相似文献   
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